Atypical endoscopic finding of colocolic intussusception: case report and literature review.

Background: Adult-onset colonic intussusception is a rarely encountered condition that leads to large intestinal obstruction with time. Patients often present with a variety of symptoms that are non-specific making it challenging to arrive at a definitive diagnosis. This is worrying as diagnostic delay could lead to a significant increase in morbidity and mortality. We wish to present and describe a case of an atypical endoscopic finding of colocolic intussusception secondary to ascending colon cancer. Case Description: Sixty-seven-year-old lady was referred for 1 month's duration of passing melenic stools with mucus followed by a week's complain of hematochezia. Clinical examination and other relevant blood results were unremarkable except for iron deficiency anemia. Initial colonoscopy revealed a large mass within the splenic flexure with inconclusive biopsies. A more detailed colonoscopy repeated the following day revealed a massive, black-to-yellowish lesion within the splenic flexure with no viable mucosa seen. Colonic bezoar was initially suspected, however various endoscopic retrieval methods proved futile. Switching to a slimmer diagnostic gastroscope, the colon was carefully negotiated until a large ulcer was found within the ascending colon, adjacent to the mass' origin. An emergency CT abdomen and subsequently extended right hemicolectomy performed revealed a colocolic intussusception with sealed perforation secondary to an ascending colonic mass acting as an intussusceptum. Histopathology evaluation confirmed an ascending colon adenocarcinoma (pT2N0M0) amidst a background of extensive ischemic changes. Conclusions: Endoscopic descriptions of colonic intussusception are unusual given their rarity. Furthermore, these lesions can mimic a colonic bezoar as a result of fecal accretion and this can ultimately lead to false diagnostic and therapeutic decisions. In such instances, clarification with a CT scan before management decision can potentially avert unnecessary endoscopic intervention and complications.

Current Status of Mucosal Imaging with Narrow-Band Imaging in the Esophagus.

Recent advances in endoscopic imaging of the esophagus have revolutionized the diagnostic capability for detecting premalignant changes and early esophageal malignancy. In this article, we review the practical application of narrow-band imaging focusing on diseases of the esophagus, including Barrett's esophagus, adenocarcinoma, and squamous cell carcinoma.

Chromoendoscopy: role in modern endoscopic imaging.

Detection of early gastrointestinal tract malignancy can be challenging on white light endoscopy especially as lesions can be subtle and inconspicuous. With the advent of electronic chromoendoscopy technologies, lesions which have already been detected can be quickly and "conveniently" characterised. This review will discuss some of the indications and modern applications of chromoendoscopy in various conditions including Barrett's oesophagus, oesophageal squamous cell carcinoma, early gastric cancer, inflammatory bowel disease and neoplastic colonic lesions. In carefully selected situations, chromoendoscopy could still be a useful adjunct to white light endoscopy in day-to-day clinical practice.

Narrow-band imaging for scar (NBI-SCAR) classification: from conception to multicenter validation.

BACKGROUND AND AIMS: Surveillance post-endoscopic resection (ER) currently warrants biopsy samples from the resection site scar in most cases, although clinical practice is variable. A classification with standard criteria for scars has not yet been established. We aimed to create and validate a novel classification for post-ER scars by using specific criteria based on advanced imaging. METHODS: Key endoscopic features for scars with and without recurrence were (1) dark brown color, elongated/branched pit pattern, and dense capillary pattern and (2) whitish, pale appearance, round/slightly large pits, and irregular sparse vessels. Scars were first assessed with high-definition white-light endoscopy (HD-WLE) followed by interrogation with narrow-band imaging (NBI). Scars with at least 2 concordant characteristics were diagnosed with "high confidence" for NBI for scar (NBI-SCAR) classification. The final endoscopic predictions were correlated with histopathology. The primary outcome was the difference in sensitivity between NBI-SCAR and HD-WLE predictions. Secondary outcomes included the validation of our findings in 6 different endoscopy settings (Australia, United States, Japan, Brazil, Singapore, and Malaysia). The validation took place in 2 sessions separated by 2 to 3 weeks, each with 10 one-minute videos of post-ER scars on underwater NBI with dual focus. Inter-rater and intrarater reliability were calculated with Fleiss' free-marginal kappa and Bennett et al. S score, respectively. RESULTS: One hundred scars from 82 patients were included. Ninety-five scars were accurately predicted with high confidence by NBI-SCAR in the exploratory phase. NBI-SCAR sensitivity was significantly higher compared with HD-WLE (100% vs 73.7%, P < .05). In the validation phase, similar results were found for endoscopists who routinely perform colonoscopies and use NBI (sensitivity of 96.4%). The inter-rater and intrarater reliability throughout all centers were, respectively, substantial (κ = .61) and moderate (average S = .52) for this subset. CONCLUSIONS: NBI-SCAR has a high sensitivity and negative predictive value for excluding recurrence for endoscopists experienced in colonoscopy and NBI. In this setting, this approach may help to accurately evaluate or resect scars and potentially mitigate the burden of unnecessary biopsy samples.